<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>背景图</title>
    <style>
        /* 盒子是 1000 *1000 */
        div {
            width: 1000px;
            height: 1000px;

            /* 背景图默认是平铺（复制）的效果 */
            background-image: url(./背景图测试图片.jpg);
        }
    </style>
</head>
<body>
    <div>div 标签</div>
</body>
</html>